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<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>one-lease-per-client true;<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 color=navy face=Arial><span style='font-size:
10.0pt;font-family:Arial;color:navy'>deny duplicates;<o:p></o:p></span></font></p>
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10.0pt;font-family:Arial;color:navy'><o:p> </o:p></span></font></p>
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<p class=MsoNormal><b><font size=2 face=Tahoma><span style='font-size:10.0pt;
font-family:Tahoma;font-weight:bold'>From:</span></font></b><font size=2
face=Tahoma><span style='font-size:10.0pt;font-family:Tahoma'>
dhcp-users-bounce@isc.org [mailto:dhcp-users-bounce@isc.org] <b><span
style='font-weight:bold'>On Behalf Of </span></b>schilling<br>
<b><span style='font-weight:bold'>Sent:</span></b> Friday, September 12, 2008
1:43 PM<br>
<b><span style='font-weight:bold'>To:</span></b> <st1:PersonName w:st="on">dhcp-users@isc.org</st1:PersonName><br>
<b><span style='font-weight:bold'>Subject:</span></b> DHCP leases exhaustion
attack?</span></font><o:p></o:p></p>
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12.0pt'><o:p> </o:p></span></font></p>
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<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Hi All,<br>
<br>
We had a case that one MAC address obtained about 100 IP address from our DHCP
server in a short time period. We noticed that some DHCP requests come with
different Windows Netbios name. If the client manually send DHCP request asking
for different IP addresses, will ISC DHCPD just give to them without checking
the current lease file that the same MAC already has a lease? Or will ISC DHCPD
has a option to limit how many IP could be associated with a MAC?<br>
<br>
I saw Yersinia tool can send DHCP request, but I did not try it out yet. Will
that tool hack the DHCP server similar to our case?<br>
<br>
Thanks.<br>
<br>
Schilling<o:p></o:p></span></font></p>
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